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by psychometry 4089 days ago
I don't write C at all but aren't there code analysis tools that catch things like this? Some kind of standard code linting library, maybe?
2 comments
andrewchambers 4089 days ago
Yes, the point is that these are obvious flaws, and dlink didn't even fix them. Someone from the dlink team just sucks.

edit: And that someone may not even be the developer, at the end of the day, the company does not have the systems in place for quality control.

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jheriko 4089 days ago
Yes there are these things, although usually more focused on C++ these days.

Compiling C as C++ with a C++ compiler is not a bad idea though... many compilers which will deal with both and tend not to care about pure C very much at all. Modern, extremely popular compilers may not even support C89 features yet... not to mention that lots will allow dangerous things like returning nothing from a function with a non void return type without even a compile error.

Many tools can catch the bugs mentioned here though - things like PVS studio, cppcheck, or the built in visual studio or xcode analysers (I would never recommend pc-lint, sorry), and some of these things mentioned are compiler warnings in some cases (sprintf will trigger the endlessly annoying CRT_NO_SECURE_WARNINGS message from the ms compiler for instance).

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rpcope1 4089 days ago 

  Modern, extremely popular compilers may not even support C89 features yet...
Citation needed please. Also, because C is not a true subset of C++, it has seemed that many big C projects will not compile on C++ compilers because of corner cases, so this may be something to watch for. Much of the incompatibility rises from additions in C99.

References: (http://www.geeksforgeeks.org/write-c-program-wont-compiler-c..., http://david.tribble.com/text/cdiffs.htm#C90-vs-CPP98)

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jheriko 4088 days ago
well spotted, that should have been C99, of which many features are not supported with the ms compiler. i believe that the variable array thing was pulled in C11 because so few compilers ever bothered to support it...

i see problems with it regularly where we use c code that goes through clang just fine, but cl complains. not putting declarations at the top of a file or scope is the obvious example that comes to mind and constantly snags people...

that being said there are even C++ problems, although smaller. for instance, its impossible to use the preprocessor variadic macros across cl, clang, gcc without getting warnings from at least one of them. i like to run with warnings as errors and the highest warning settings possible.

i'm not going to bother digging up references for informal conversation... but thanks for catching the mistake.

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